While not limited thereto, the present invention is particularly adapted for use in a power supply for control systems such as those used on hydrofoil seacraft, aircraft and the like where safety is a paramount consideration. In a hydrofoil craft, for example, reliability is vitally important in the roll control system. Such a roll control system comprises sensing means for sensing motion of the craft about the roll axis and means responsive to the signals generated by the sensing means to effect the desired movement of the control surfaces on the foils of the craft to counteract the rolling motion and stabilize the craft about its roll axis. In case of a failure or malfunction in this roll control system, an unsafe condition can develop in which the motion of the craft becomes unstable; and the craft can exhibit divergent motions such that it may impact the water with angular rates of motion and attitudes that can endanger personnel on board the craft or cause possible damage to the craft itself.
In a control system of the type described above, the power supply utilized must supply many loads isolated from each other. At the same time, these loads must be capable of being momentarily or continuously shorted followed by a rapid recovery to normal operation after the short is removed. Additionally, a short on any circuit must not affect operation of any other circuit.
In the past, the problem of load isolation in a system of this type has been attacked by providing a series inductor for each load requiring excitation. This provides current limiting and isolation but introduces poor voltage regulation. Other techniques for accomplishing the same result ultilize complicated electronic regulators; however these are not altogether satisfactory and are expensive.